JP2002346591A - Sewage treatment apparatus and operating method thereof - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent a decrease in the total amount of organisms in a carrier fluidizing tank, and to recover the decreased total amount of organisms after backwashing of a filter carrier in a filtration tank in an early stage, so that it is always stably covered. Provided are a sewage treatment apparatus capable of efficiently decomposing treated water and an operation method of the sewage treatment apparatus. An anaerobic treatment tank for anaerobically treating water to be treated is provided.
A carrier fluidizing tank E1 for accommodating a carrier C1 carrying microorganisms capable of flowing together with the anaerobic water to be treated and providing an air diffuser D1 for supplying air bubbles to the carrier C1; Downstream, is provided with a filtration tank E2 having a sediment filtration layer formed in a state where a plurality of filtration carriers are settled and deposited inside, and the water to be treated flowing out from the carrier fluidization tank E1 and A sewage treatment apparatus provided with an air lift pump A3 capable of transferring sludge to a carrier fluidizing tank E1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anaerobic treatment tank for anaerobically treating water to be treated, a carrier carrying microorganisms capable of flowing together with the anaerobic treated water to be treated, and supplying air bubbles to the carrier. A carrier flow tank for aerobic treatment with a diffuser, and a filtration tank on the downstream side of the carrier flow tank, on which a plurality of filtration carriers are settled and deposited inside to form a sedimentation filtration layer. The present invention relates to a provided sewage treatment apparatus.

[0002]

2. Description of the Related Art Conventionally, this type of sewage treatment apparatus is most typically applied to a household septic tank.
In other words, the water to be treated, which is the inflowing wastewater, is received in a sedimentation separation tank or an anaerobic filter bed tank, and is subjected to anaerobic treatment. A septic tank having a structure capable of sufficiently performing biological treatment in the tank is used as one suitable for purifying various kinds of sewage.

As such a purification tank, as shown in FIG. 6, an anaerobic treatment tank N, an aerobic treatment tank E, and a treatment water tank T are arranged from the upstream side.
1, an anaerobic treatment tank N is provided, and the anaerobic treatment tank N is provided with an anaerobic filter bed tank first chamber N3 and an anaerobic filter bed tank second chamber N4 in parallel, and the aerobic treatment tank E is provided with a carrier fluidizing tank E1. And a purification tank in which a filtration tank E2 is disposed vertically.

In this purification tank, a diffusion tube D1 is provided at the bottom of the carrier fluidization tank E1, and a cleaning air lift pump P1 is provided at the top.
Is provided. Further, the upper end of the suction pipe H inserted and vertically installed is connected to the air lift pump P1, and the suction pipe H
Is connected to a transfer pipe W whose tip is directed toward the upper side of the first anaerobic filter bed tank N1.

The raw water to be treated flows into the first anaerobic filter bed tank N3 from the raw water inflow section I, and also enters the second anaerobic filter bed tank N4, the carrier fluidizing tank E1, the filtration tank E2, and the treated water tank T1. After being sequentially decomposed while being transferred to the downstream, it is decomposed, passed through a disinfecting tank Q provided above the treated water tank T1, and then discharged from the discharge port Z to the outside of the tank.

The anaerobic filter tank first chamber N3 is configured to be able to store the raw water flowing into the to-be-processed water, so that anaerobic microorganisms can be grown therein. Anaerobic filter bed first room N
The raw water to be treated flowing into the tank 3 is the first anaerobic filter bed tank N3.
And is anaerobically decomposed, and mainly coarse organic matter is subdivided.

The anaerobic filter bed second chamber N4 is provided with an anaerobic filter bed F
And an anaerobic microorganism is fixedly maintained on the anaerobic filter bed and grown. The water to be treated, which has flowed into the anaerobic filter bed second chamber N4, is further subjected to anaerobic treatment and is decomposed to a state where there is almost no solid matter.

[0008] The carrier fluidizing tank E1 holds and holds a carrier which is formed to be flowable together with the water to be treated in a state in which microorganisms are supported, and also has an air supply pipe for flowing the carrier by supplying bubbles. A diffuser is provided with the connected diffuser tube D1 provided therein, and the carrier is caused to flow in the carrier flow tank E1 by supplying bubbles from the diffuser. With such a configuration, the water to be treated flowing into the carrier fluidization tank E1 is purified by aerobic decomposition by aerobic microorganisms. The water to be treated which has undergone such treatment flows downward in the tank and flows into the filtration tank E2.

The water to be treated containing sludge flowing to the filtration tank E2 is filtered through the sediment filtration layer on which the carrier is deposited, and contains almost no solid content. Advected.

The treatment water tank T1 is provided with the carrier filtration tank E2.
Only the clean supernatant that has passed through can be released to the outside,
The water to be treated that has flowed into the disinfecting tank Q provided above the treated water tank T1 contacts the solid disinfectant, is disinfected, and is discharged outside the tank.

Further, at the time of washing the carrier for removing the sludge which adheres to the carrier on which the deposited filtration layer is formed and causes clogging, the filtration carrier is removed by air coming out of a backwash pipe at the lower portion of the filtration tank E2. The air is removed from the anaerobic filter bed tank by operating the air lift pump P1, sucking sewage from the suction port at the lower end of the suction pipe H, and draining the backwash water after the backwash through the transfer pipe W. Had been transferred to N3.

Further, as a conventional example, Japanese Patent Application Laid-Open No.
86, JP-A-5-269482, JP-A-5-269482
No. 309382.

[0013]

According to the conventional septic tank described above, the sludge in the carrier fluidizing tank flows in the carrier fluidizing tank together with the carrier by the supply of bubbles from the diffuser pipe. It easily flows to the downstream filtration tank, and in that case, the sludge residence time in the carrier fluidization tank is short, so that the efficiency of BOD decomposition treatment may be reduced. Further, when the sludge is transferred to the filtration tank, it causes a decrease in the total amount of organisms in the carrier fluidization tank. This tendency is particularly strong when aerobic treatment is performed on high-load treated water, and the water to be treated including the nitrification capacity is increased. However, there is a problem that the decomposition processing capability of the compound is increased. Here, the term “sludge” is a general term for suspended organic and inorganic substances carrying microorganisms that contribute to biological treatment.

Further, when backwashing is performed to remove sludge that adheres to the filtration carrier in the filtration tank and causes clogging, the backwash wastewater containing the separated sludge is subjected to the anaerobic treatment. When transferred to the filter bed tank first chamber, the sludge is settled and stored in the anaerobic filter bed tank first chamber as excess sludge, and the total amount of organisms in the filter tank for biodegrading dissolved components in the water to be treated temporarily decreases. Therefore, there is a problem that the treatment efficiency in the filtration tank after backwashing is reduced, and the SS removal efficiency by biological filtration is easily reduced due to the relatively small amount of suspended solids (SS) in the filtration tank. was there.

[0015] Accordingly, an object of the present invention is to prevent a decrease in the total amount of organisms in the carrier fluidization tank and to recover the decreased total amount of organisms after backwashing of the filtration carrier in the filtration tank in an early stage, so that it is always stable. Another object of the present invention is to provide a sewage treatment apparatus capable of efficiently decomposing water to be treated and a method of operating the sewage treatment apparatus.

[0016]

[Means for Solving the Problems] [Structure 1] A feature structure of the present invention for achieving this object is as described in claim 1, wherein an anaerobic treatment tank for anaerobically treating water to be treated, A carrier fluidized vessel containing a carrier carrying microorganisms that can flow with the treated water, and a carrier fluidizing tank provided with an air diffuser for supplying air to the carrier for aerobic treatment, and a plurality of filtrations downstream of the carrier fluidizing vessel. In a sewage treatment apparatus provided with a filtration tank in which a sediment filtration layer is formed in a state in which the carrier is settled and deposited inside, the water to be treated and sludge flowing out of the carrier flow tank can be transferred to the carrier flow tank. There is a first advection mechanism, and its operation and effect are as follows.

[Function and Effect 1] That is, by providing a first advection mechanism capable of transferring the water to be treated and sludge flowing out of the carrier fluidizing tank to the carrier fluidizing vessel, the water to be treated flowing out of the carrier fluidizing vessel is provided. And the sludge can be transferred into the carrier fluidization tank. Thereby, even when the sludge is transferred to the downstream tank of the carrier fluidization tank, it is possible to prevent a decrease in the total amount of organisms in the carrier fluidization tank due to the transfer of the sludge by the first advection mechanism. In this way, by preventing the total amount of living organisms from decreasing, the chances of contact between microorganisms and the water to be treated are increased, and the efficiency of BOD treatment in the treated water is improved. it can. Furthermore, since the nitrification reaction of the ammonia component in the water to be treated can be promoted, the decomposition treatment capacity of the water to be treated can be improved. Further, a part of the sludge multiplies in the carrier fluidization tank and flows to the filtration tank. Therefore, the total amount of living organisms reduced after the backwashing of the filtration carrier in the filtration tank can be recovered at an early stage. By recovering the reduced total amount of organisms, the efficiency of decomposing and removing SS is improved, so that a filtration treatment can be performed under favorable conditions. Further, the oxygen supply amount in the filtration tank also increases, so that the purification efficiency in the filtration tank can be improved.

[Structure 2] In order to achieve this object, the present invention is characterized in that an anaerobic treatment tank for anaerobically treating the water to be treated, A carrier fluidizing tank for accommodating a carrier carrying possible microorganisms and having an aeration unit for supplying air to the carrier, and a plurality of filtration carriers sedimented and deposited inside the carrier fluidizing tank downstream of the carrier fluidizing tank; In a sewage treatment apparatus provided with a filtration tank in which a sediment filtration layer is formed in a state where the carrier flow tank and the filtration tank, between the carrier flow tank and the filtration tank, to prevent the carrier from flowing to the filtration tank, A first advection mechanism that has a separation unit that suppresses advection of sludge in the carrier fluidization tank to the filtration vessel, and that can transfer treated water and sludge flowing out of the carrier fluidization vessel to the carrier fluidization vessel. The effect is as follows. It is.

[Function and effect 2] That is, between the carrier flow tank and the filtration tank, the carrier is prevented from flowing to the filtration tank, and the sludge in the carrier flow tank is moved to the filtration tank. If there is a separation unit that suppresses, the separation unit,
Since the sludge is difficult to easily flow from the carrier fluidization tank to the filtration tank, the residence time of the sludge in the carrier fluidization vessel increases, and furthermore, the water to be treated and the sludge flowing out of the carrier fluidization vessel are removed. If a first advection mechanism that can be transferred to the carrier flow tank is provided, the first advection mechanism allows the water to be treated and sludge flowing out of the carrier flow tank to be transferred into the carrier flow tank, The configuration is such that a decrease in the total amount of organisms in the carrier fluidization tank can be prevented.
Therefore, as compared with the above-described configuration 1, a decrease in the total amount of organisms in the carrier fluidization tank can be more effectively prevented, and thus the BOD treatment, the nitrification reaction of the ammonia component, and the decomposition and removal of SS are further promoted. Can be done.

[Structure 3] In order to achieve this object, the present invention is characterized in that, in the structure 1 and 2 described above, the water to be treated and the sludge flowing out of the carrier fluidizing tank are separated by the method described above. The point that a second advection mechanism capable of transferring to the anaerobic treatment tank is provided is provided, and its operation and effect are as follows.

[Function and Effect 3] In other words, if a second advection mechanism capable of transferring the water to be treated and sludge flowing out of the carrier flow tank to the anaerobic treatment tank is provided, Water and sludge can be transferred into the anaerobic treatment tank. As a result, the transferred treated water is
Since denitrification can be performed in the anaerobic treatment tank, the nitrogen component can be removed, and the transferred sludge can be settled and stored in the anaerobic treatment tank as excess sludge.

[Structure 4] According to a fourth aspect of the present invention, there is provided a backwashing device for removing sludge adhering to the filter carrier, wherein the first advection mechanism is provided. And a method of operating the sewage treatment apparatus for operating the sewage treatment apparatus according to Configuration 3, wherein the control of the transfer of the water to be treated and the sludge of the second advection mechanism is performed in accordance with the timing of backwashing. During or after backwashing to remove sludge adhering to the filtration carrier, the water to be treated in the filtration tank and the sludge are transferred to the carrier fluidization tank for a predetermined time, and after a predetermined time, the water to be treated in the filtration tank The operation is performed by transferring the sludge to the anaerobic treatment tank, and the operation and effect are as follows.

[Effect 4] In other words, in the sewage treatment apparatus according to the configuration 3, if a backwashing device for removing sludge adhering to the filtration carrier is provided, the backwashing device can backwash the filtration carrier. By releasing water or bubbles, create a situation in which the filtration carriers collide with each other,
By removing the sludge causing clogging attached to the carrier by its collision action, the filter carrier is regenerated,
The filtering function can be restored again. Therefore, the filtration of the water to be treated in the filtration tank can be performed under favorable conditions.

Further, by providing a control mechanism for controlling the transfer of the water to be treated and the sludge of the first advection mechanism and the second advection mechanism in accordance with the timing of the backwash, Control can be performed such that only the first advection mechanism is activated, only the second advection mechanism is activated, or both the first and second advection mechanisms are activated. By controlling the operation of the first advection mechanism and the second advection mechanism at the time of backwashing or after backwashing, the sludge separated from the filtration carrier is efficiently removed from the filtration carrier, the carrier fluidization tank, or the anaerobic treatment tank Can be transferred to

[0025] In the sewage treatment apparatus having the above-described configuration, the water to be treated and the sludge in the filtration tank are supplied to the carrier fluidization tank at the time of backwashing or after backwashing in which the sludge attached to the filtration carrier is separated. By transferring the time, the sludge and the water to be treated separated by the backwash in the filtration tank are transferred to the carrier fluidization tank by the first advection mechanism, so that the amount of sludge in the carrier fluidization vessel is increased. After a lapse of a predetermined time, the circulation mode may be switched to the second advection mechanism to transfer the water to be treated in the filtration tank and the sludge to the anaerobic treatment tank.

At this time, by appropriately setting the predetermined time, the amount of sludge in the carrier flow tank or the filtration tank can be controlled. For example, when the amount of sludge in the carrier fluidized tank is small, a longer time is set for transferring sludge to the carrier fluidized vessel by the first advection mechanism, and the amount of sludge in the carrier fluidized vessel is adjusted to an appropriate amount. When it reaches, the transfer of the water to be treated and the sludge can be switched to the second advection mechanism and transferred to the anaerobic treatment tank, and the sludge can be precipitated and stored as excess sludge in the anaerobic treatment tank. The predetermined time can be determined, for example, according to the inflow load of the water to be treated.

After the backwashing of the filter carrier, the total amount of organisms in the filtering tank is temporarily reduced. However, the separated sludge generated by the backwashing is transferred to the anaerobic treatment tank and settled and stored. Not only, it is transferred to the carrier fluidization tank and retained,
Some of the sludge multiplies in the carrier fluidization tank and flows to the filtration tank. Therefore, the total amount of living organisms reduced after the backwashing of the filtration carrier in the filtration tank can be recovered at an early stage. By recovering the reduced total amount of organisms, the efficiency of decomposing and removing SS is improved, so that a filtration treatment can be performed under favorable conditions.

By operating in this manner, biological treatment is stable, and even high-load treated water can be treated efficiently. Further, by appropriately setting the predetermined time, the amount of sludge in the carrier fluidizing tank and the filtration tank can be controlled, so that a wide range of operation methods can be adopted.

[Structure 5] In order to achieve this object, the present invention is characterized in that a backwashing device for removing sludge adhering to the filter carrier is provided, and the first advection mechanism is provided. And a method of operating the sewage treatment apparatus for operating the sewage treatment apparatus according to Configuration 3, wherein the control of the transfer of the water to be treated and the sludge of the second advection mechanism is performed in accordance with the timing of backwashing. At the time of backwashing or after backwashing to remove sludge attached to the filtration carrier, the method is to operate by a method of transferring treated water and sludge of the filtration tank to the carrier fluidization tank and the anaerobic treatment tank at a predetermined ratio. The effects are as follows.

[Effect 5] That is, in the sewage treatment apparatus according to the configuration 3, the backwashing apparatus for removing the sludge adhering to the filter carrier, and the processing of the first advection mechanism and the second advection mechanism The operation and effect provided with the control mechanism for controlling the transfer of water and sludge in accordance with the timing of backwashing are as described in the operation and effect 4 above.

In the sewage treatment apparatus having the above-mentioned structure, the water to be treated and the sludge in the filtration tank are removed at a predetermined ratio during or after backwashing to remove the sludge attached to the filtration carrier. By transferring to the tank and the anaerobic treatment tank, to transfer the sludge and water to be treated separated by backwashing in the filtration tank to the carrier flow tank by the first advection mechanism, in the carrier flow tank The amount of sludge can be increased. At the same time, a circulation operation of transferring the sludge and the water to be treated separated by backwashing in the filtration tank to the anaerobic treatment tank by the second advection mechanism can be performed.

At this time, by appropriately setting the transfer ratio of the first advection mechanism and the second advection mechanism, it is possible to control the amount of sludge in the carrier fluidization tank and the filtration tank. For example, when the amount of sludge in the carrier fluidization tank is small, the rate at which the sludge is transferred to the carrier fluidization tank by the first advection mechanism is determined by the rate at which the sludge is transferred to the anaerobic treatment tank by the second advection mechanism. It is possible to set many. At this time, a part of the sludge transferred to the carrier fluidization tank multiplies in the carrier fluidization vessel and flows to the filtration vessel. Therefore, the total amount of living organisms reduced after the backwashing of the filtration carrier in the filtration tank can be recovered at an early stage.

The transfer ratio can be determined, for example, according to the inflow load of the water to be treated. At this time, when the inflow load is high, the rate of transferring the sludge to the anaerobic treatment tank by the second advection mechanism is increased from the rate of transferring the sludge to the carrier flow tank by the first advection mechanism, and the inflow load is increased. When it is low, it is possible to make the ratio of transferring the sludge to the carrier fluidizing tank by the first advection mechanism larger than the ratio of transferring the sludge to the anaerobic treatment tank by the second advection mechanism.

By operating in this manner, biological treatment is stable, and even high-load treated water can be treated efficiently. Further, by appropriately setting the transfer ratio, the amount of sludge in the carrier fluidizing tank and the filtration tank can be controlled, so that a wide range of operation methods can be adopted.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. As shown in FIG. 1, the sewage treatment tank constituting the sewage treatment apparatus of the present invention includes an anaerobic treatment tank N, a carrier flow tank E1, a carrier filtration tank E2, a treatment water tank T1,
It has a disinfecting tank Q, a discharge pump tank S, and a solid-liquid separation tank N1 and an anaerobic filter bed tank N2 as the anaerobic treatment tank N.

The raw water to be treated flows into the solid-liquid separation tank N1 from the raw water inflow section I, and is transferred downstream in the order of the anaerobic filter bed tank N2, the carrier fluidization tank E1, the carrier filtration tank E2, and the treated water tank T1. After being decomposed while passing through the disinfecting tank Q and the discharge pump tank S, it is discharged from the discharge port Z to the outside of the tank.

The solid-liquid separation tank N1 is provided with a water inlet I to be treated.
Water is temporarily stored after receiving the water to be treated which flows in from there, and a water treatment space for sedimentation and separation of impurities is provided. The suspended solids and solids in the raw water that has flowed into the raw water are settled and separated as scum on the upper part of the solid-liquid separation tank N1.
Alternatively, it is stored as sludge at the bottom. Further, the solid-liquid separation tank N1 and the anaerobic filter bed tank N2 have a relatively large storage capacity, and have a flow rate adjusting unit R capable of adjusting the flow rate in the range of LWL to HWL. Thereby, since it is configured to absorb the peak amount of the inflowing treated water amount concentrated at a specific time in the morning and evening, it contributes to stabilization of the processing performance of the downstream carrier fluidizing tank E1 and the downstream carrier filtering tank E2. .

Instead of the solid-liquid separation tank N1, an anaerobic filter bed provided with an anaerobic filter bed may be used. At this time, anaerobic microorganisms can be grown inside the anaerobic filter bed. The raw water to be treated flowing into the anaerobic filter bed tank is stored in the anaerobic filter tank, is anaerobically decomposed, and mainly coarse organic matter is subdivided. Solids such as sludge that is not easily decomposed are stored as sediment at the lower part of the anaerobic filter tank or as scum at the upper part of the anaerobic filter tank.

The anaerobic filter bed tank N2 is provided with an anaerobic filter bed F, and anaerobic microorganisms are fixedly held on the anaerobic filter bed F and grown. The anaerobic filter bed tank N
The to-be-processed water which has flowed into 2 is further subjected to anaerobic treatment, decomposed to a state in which there is almost no solid matter, and then is transferred to the carrier fluidizing tank E1 via a flow rate adjusting air lift pump A1.

As the anaerobic treatment tank, it is also possible to provide a flow rate adjusting tank instead of the solid-liquid separation tank N1 and the anaerobic filter bed tank described above to absorb the peak amount of the water to be treated in the entire tank. . At this time, a sludge concentration storage tank may be separately provided to sediment and store solids in the water to be treated.

The carrier fluidizing tank E1 holds and holds the carrier C1 which is formed so as to be able to flow together with the water to be treated in a state in which the microorganisms are carried, and an air supply pipe for flowing the carrier by supplying air bubbles. Diffuser D1 connected to
And a diffuser is provided therein, and the carrier C1 is caused to flow in the carrier fluidizing tank E1 by supplying air bubbles from the diffuser. With such a configuration, the water to be treated flowing into the carrier fluidization tank E1 is purified by aerobic decomposition by aerobic microorganisms. If the carrier C1 has a shape with surface irregularities, the carrier C1 has a preferable shape for supporting a biofilm on the surface of the carrier C1.

The carrier filtration tank E2 is formed by filling a carrier C2 having a specific gravity greater than that of water at a high density to a predetermined height. Thereby, the water to be treated including the sludge flowing to the carrier filtration tank E2 is filtered through the sediment filtration layer on which the carrier C2 has been deposited, and is substantially free of solids. It is transferred to the water tank T1. In the lower part of the carrier filtration tank E2, a backwash tube D2 that diffuses air to remove sludge that causes clogging adhered to the carrier C2 is provided as a backwash device for the carrier C2.
The air diffuser D1 and the backwash tube D2 are preferably capable of adjusting the amount of air bubbles supplied.

The backwashing of the carrier C2 by the backwashing tube D2 is performed, for example, by connecting a timer to the backwashing tube D2 and periodically operating the backwashing tube D2 to backwash the carrier C2. You may. Further, the frequency of backwashing can be appropriately determined depending on the season or the inflow load.

When the carrier C2 has a smooth surface, sludge causing clogging at the time of back washing is easily peeled off, and the filtration area can be freely designed.

Further, an air lift pump A2 is provided as a transfer mechanism for transferring the water to be treated and the sludge to the solid-liquid separation tank N1, and the water and the sludge are transferred to the carrier fluidizing tank E1. An air lift pump A3 is provided as an advection mechanism. The air lift pump A2
Is configured so that the water to be treated and the sludge at the lower portion of the carrier filtration tank E2 can be circulated in the solid-liquid separation tank N1 by a fixed amount at the time of normal treatment, and the water to be treated transferred to the solid-liquid separation tank N1 is Since the denitrification is performed in the solid-liquid separation tank N1, the nitrogen component can be removed, and the transferred sludge can be settled and stored in the anaerobic treatment tank as excess sludge. On the other hand, the air lift pump A3
The water to be treated and the sludge flowing out of the carrier flow tank E1 and flowing into the carrier filtration tank E2 can be transferred to the carrier flow tank E1. Since the transfer of the sludge can prevent a decrease in the total amount of organisms in the carrier fluidization tank E1,
The chance of contact between microorganisms and treated water increases,
The processing efficiency of OD is improved, and even high-load treated water can be efficiently decomposed. Furthermore, the nitrification reaction of the ammonia component in the water to be treated can be promoted. Further, by preventing a decrease in the total amount of organisms in the carrier fluidization tank E1, the decomposition efficiency of organic components and the like is increased, and the oxygen supply amount in the carrier filtration vessel E2 is also increased, so that the purification efficiency in the carrier filtration vessel E2 is increased. Can be improved.

It is possible to provide a control mechanism for controlling the transfer of the water to be treated and the sludge of the air lift pumps A2 and A3 in accordance with the timing of the backwash. The control mechanism can be used, for example, as long as it is configured to control the air supply from the air supply device to the air lift pump A2 and the air lift pump A3 during or immediately after the backwash.

The treated water tank T1 is configured to be able to separate the separated sludge and prevent the sludge from flowing out. Only the clean supernatant that has passed through the carrier filtration tank E2 can be transferred to the disinfecting tank Q. The water to be treated that has flowed into the disinfecting tank Q is contacted with the solid disinfectant and disinfected, and then flows into the discharge pump tank S in which the discharge pump P2 is installed. In the discharge pump tank S,
After temporarily storing the sterilized water to be treated, the water is discharged from the discharge port Z to the outside of the tank.

In the above-mentioned septic tank, the water to be treated and the sludge in the carrier filtration tank E2 are removed from the carrier flow tank E1 during or after backwashing to remove the sludge adhering to the carrier C2.
To the carrier filtration tank E after a lapse of a predetermined time.
2 to transfer the water to be treated and sludge to the solid-liquid separation tank N1, or vice versa, that is, the carrier filtration tank E2
Is transferred to the solid-liquid separation tank N1 for a predetermined time, and after a lapse of a predetermined time, the water and the sludge to be treated in the carrier filtration tank E2 are transferred to the carrier fluidization tank E1 to operate. In addition, it is possible to prevent a decrease in the total amount of organisms in the carrier fluidizing tank E1, and to quickly recover the decreased amount of organisms after the backwashing of the filtration carrier in the carrier filtration tank E2.

That is, the carrier C in the carrier filtration tank E2
During or after backwashing of 2, the sludge separated from the carrier C2 floats in the carrier filtration tank E2 and gradually sinks to the bottom. By starting the air supply to the air lift pump A3 during or after backwashing, the sludge settled at the bottom can be transferred to the carrier fluidization tank E1 together with the water to be treated, so that the total amount of organisms in the carrier fluidization vessel E1 Can be prevented from decreasing.

A predetermined time for transferring the sludge to the carrier fluidizing tank E1 is appropriately set, and after the set predetermined time has elapsed, the air supply to the air lift pump A3 is stopped and the air supply to the air lift pump A2 is started. By performing the circulation operation of transferring the sludge settled to the bottom to the solid-liquid separation tank N1 together with the water to be treated by the air lift pump A2, the amount of sludge in the carrier fluidization tank E2 can be adjusted. The sludge transferred at this time can be precipitated and stored in the solid-liquid separation tank N1 as surplus sludge.

A part of the sludge transferred to the carrier fluidizing tank E2 grows in the carrier fluidizing vessel E2,
In the carrier filtration tank E2, the total amount of organisms decreased after the backwashing of the filtration carrier can be recovered at an early stage. Therefore, the environment in which the sedimentary filtration layer captures SS and performs biological filtration can be prepared at an early stage, and the filtration capacity in the carrier filtration tank E2 can be improved on average. The start and stop of the air supply of the air lift pump A2 and the air lift pump A3 are as follows:
The control can be performed by the control mechanism.

Further, at the time of backwashing or after backwashing to remove sludge adhering to the carrier C2, the water to be treated in the carrier filtration tank E2 and the sludge are separated by a predetermined ratio into the carrier fluidizing tank E1 and the solid-liquid separation tank N1. Prevent the decrease in the total amount of organisms in the carrier fluidization tank E1 also by operating in a method of transferring to
In the carrier filtration tank E2, the total amount of organisms reduced after backwashing the filtration carrier can be recovered at an early stage.

That is, the carrier C in the carrier filtration tank E2
During or after backwashing of 2, the sludge separated from the carrier C2 floats in the carrier filtration tank E2 and gradually sinks to the bottom. By starting the air supply of the air lift pump A3 during or after backwashing, the sludge settled at the bottom can be transferred to the carrier fluidizing tank E1 together with the water to be treated. The drop can be prevented. At this time, the air lift pump A2
Air is also supplied to the air lift pump A2
The sludge transferred by the method can be precipitated and stored in the solid-liquid separation tank N1 as surplus sludge.

A part of the sludge transferred to the carrier fluidizing tank E2 grows in the carrier fluidizing vessel E2,
In the carrier filtration tank E2, the total amount of organisms decreased after the backwashing of the filtration carrier can be recovered at an early stage. Therefore, the environment in which the sedimentary filtration layer captures SS and performs biological filtration can be prepared at an early stage, and the filtration capacity in the carrier filtration tank E2 can be improved on average. The start and stop of the air supply of the air lift pump A2 and the air lift pump A3 are as follows:
The control can be performed by the control mechanism.

By operating according to the above-described method, biological treatment is stabilized, and even high-load treated water can be treated efficiently. Further, by appropriately setting the sludge transfer ratio of the air lift pump A2 and the air lift pump A3 for the predetermined time, the amount of sludge in the carrier fluidization tank E1 can be controlled, and thus a wide range of operation methods is employed. can do.

The transfer rate can be determined according to the inflow load of the water to be treated. At this time, when the inflow load is high, the rate at which the sludge is transferred to the solid-liquid separation tank N1 by the air lift pump A2 is determined by the air lift pump A2.
In step 3, the rate of transferring the sludge to the carrier fluidizing tank E1 is increased. When the inflow load is low, the air lift pump A3
The rate at which the sludge is transferred to the carrier fluidizing tank E1 is set to be greater than the rate at which the sludge is transferred to the solid-liquid separation tank N1 by the air lift pump A2.

[Other Embodiment 1] Another embodiment will be described below. The carrier C1 is prevented from flowing into the carrier filtration tank E2 between the carrier fluidization tank E1 and the carrier filtration tank E2, and the sludge in the carrier fluidization tank E1 is removed from the carrier filtration tank E2.
It is possible to provide a separation part B which suppresses advection to the air. As shown in FIG. 2, the separation section B has a configuration in which water to be treated from the carrier fluidization tank E1 flows in an overflow by an overflow section 1 provided with a slit-shaped section 2. The slit-shaped portion 2 only needs to be configured to prevent the advection of the carrier C1 in the carrier flow tank E1, and to suppress the advection of the sludge in the carrier flow tank E1 to some extent. Thus, by providing the separation part B and suppressing the advection of the sludge in the carrier fluidizing tank E1 to a certain extent, the residence time of the sludge in the carrier fluidizing vessel E1 is prolonged. Since the contact efficiency increases and the processing efficiency of BOD in the water to be treated is improved, the water can be efficiently decomposed even with high-load treated water. Furthermore, the nitrification reaction of the ammonia component in the water to be treated can be promoted.

Further, since the residence time of the sludge in the carrier fluidizing tank E1 is prolonged, the SS decomposition efficiency is increased. Therefore, the SS load in the carrier filtering vessel E2 is reduced and the SS load in the carrier filtering vessel E2 is reduced. Filtration efficiency can be improved.

In the separation section B, a transfer mechanism for transferring the sludge and the water to be treated stored at the bottom of the separation section B to the solid-liquid separation tank N1 and the carrier flow tank E1, which are anaerobic treatment tanks, respectively. It is also possible to provide an air lift pump A4 and an air lift pump A5. These air lift pumps supply air to the air lift pump A5 for a predetermined time, for example, once every several hours, and transfer the sludge settled to the bottom together with the water to be treated to the carrier fluidizing tank E1. By stopping the air supply to the air lift pump A5 and starting the air supply to the air lift pump A4, the sludge settled at the bottom is removed by the air lift pump A4 together with the water to be treated into the solid-liquid separation tank N.
It is possible to operate in a transfer-to-one manner.

It is also possible to operate in such a manner that the sludge settled at the bottom is always transferred to the solid-liquid separation tank N1 and the carrier flow tank E1 by the air lift pump A4 and the air lift pump A5 at a predetermined ratio. is there.

At this time, as shown in FIG. 7, it is also possible to provide a flow rate control tank X instead of the solid-liquid separation tank N1, and to provide a sludge concentration storage tank Y instead of the anaerobic filter bed tank N2. It is. The flow control tank X has a flow control pump P3
Has been provided, intermittent aeration to promote the vaginal removal process, alleviate inflow fluctuations, and further, in the sludge concentration storage tank Y,
Stores impurities and excess sludge. In such a configuration, the water to be treated and the sludge in the carrier filtration tank E2 can be transferred to the sludge concentration storage tank Y by an air lift pump A2, and can be transferred to the carrier flow tank E1 by an air lift pump A3. The water to be treated and the sludge in the separation section B can be transferred to the flow control tank X by an air lift pump A4, and can be transferred to the carrier flow tank E1 by an air lift pump A5. In addition, the upstream part of the said flow control tank X is the aeration type | mold screen part 10 which divides and removes foreign substances, such as paper, by aeration.

[Second Embodiment] As shown in FIG. 3, the separation part B is provided at the bottom of the separation part B with the carrier fluidizing tank E.
It is also possible to adopt a configuration in which a communication section 3 communicating with the section 2 is provided. The communication portion 3 is provided with a lattice, a net, a slit, and the like to prevent the carrier C1 in the carrier flow tank E1 from advancing to the separating portion B, and to allow the advancing of the water to be treated and the sludge. If so, it is applicable. The communication part 3
The sludge that has passed through is settled and stored at the bottom of the separation section B. The stored sludge is passed through the communication section 3
Through which the sludge can be transferred to the carrier fluidizing tank E1, and the sludge deposited on the bottom of the separation section B can be transported into the carrier fluidizing vessel E1. The transfer of the sludge can prevent a decrease in the total amount of organisms in the carrier fluidization tank E1, so that the chance of contact between microorganisms and the water to be treated is increased and the efficiency of treating BOD in the water to be treated is improved. Even treated water can be decomposed efficiently. Furthermore, the nitrification reaction of the ammonia component in the water to be treated can be promoted. Further, as in the above-described another embodiment 1, in the separation section B, the sludge and the water to be treated stored at the bottom of the separation section B are separated from the solid-liquid separation tank N1 which is an anaerobic treatment tank and the carrier flow. It is also possible to provide an air lift pump A4 and an air lift pump A5 as a transfer mechanism for transferring each to the tank E2. These air lift pumps can be operated as in the first embodiment described above. With this configuration, the communication portion 3 and the air lift pump A5
Thereby, the sludge accumulated in the separation section B can be efficiently transferred to the carrier fluidizing tank E2.

[Third Embodiment] As shown in FIG. 4, the separation section B can be provided at the bottom of the carrier filtration tank E2. At this time, a communication part 3 is provided below the partition wall that separates the carrier flow tank E1 and the carrier filtration tank E2 to prevent the carrier C1 in the carrier flow tank E1 from flowing to the separation part B, and It is configured to allow the advection of treated water and sludge. The sludge that has passed through the communication section 3 is separated by the separation section B
Settles and accumulates at the bottom. The stored sludge can be freely transferred to the carrier flowing tank E1 through the communication section 3, and the sludge deposited on the bottom of the separation section B can be transferred into the carrier flowing tank E1.

[Embodiment 4] In each of the air lift pumps described in the above embodiments, as shown in FIG. 5, the inside of the air lift pipe 5 is divided in the axial direction of the pipe.
An integrated air lift pump 4 having an air supply pipe 6 connectable to an air supply device capable of supplying air to each of the plurality of divided portions 9 can also be provided. The integrated air lift pump 4 includes a horizontal pipe 7 at an upper part of the air lift pipe 5 for transferring water to be treated and sludge, and an air supply pipe 6 connectable to an air supply device capable of supplying air to a lower part.
Is provided. The inside of the air lift tube 5 is provided with a partition plate 8.
And so on, but it is not limited to such a configuration,
It is also possible to accommodate a tubular tube in the tube and divide it.
By using this one integrated air lift pump 4, it becomes possible to transfer the water to be treated and the sludge in the tank to a plurality of systems.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a septic tank constituting a sewage treatment apparatus of the present invention.

FIG. 2 is a schematic view of a separation unit of a septic tank constituting the sewage treatment apparatus of the present invention.

FIG. 3 is a schematic view of another embodiment of a separation section of a septic tank constituting a sewage treatment apparatus of the present invention.

FIG. 4 is a schematic view of another embodiment of a separation section of a septic tank constituting a sewage treatment apparatus of the present invention.

FIG. 5 is a schematic diagram of an integrated air lift pump.

FIG. 6 is a schematic side view of a conventional septic tank.

FIG. 7 is a schematic side view of another embodiment of the septic tank constituting the sewage treatment apparatus of the present invention.

[Explanation of symbols]

 N1 Solid-liquid separation tank N2 Anaerobic filter bed tank E1 Carrier flow tank E2 Carrier filtration tank T1 Treatment water tank Q Disinfection tank

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takeshi Matsuda 2 shares at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture Inside the Kubota Shiga Plant (72) Inventor Nobuhiko Nishikawa 2 shares at Takamatsu, Kosai-cho, Koga-gun, Shiga Prefecture F-term in Kubota Shiga Plant (reference) 4D003 AA14 AB02 BA02 BA03 CA02 DA09 DA22 EA01 EA14 FA05 4D027 AB07 AB14 4D040 BB07 BB24 BB42 BB54 BB65 BB82 BB91

Claims (5)

[Claims] An anaerobic treatment tank for anaerobically treating water to be treated,
The carrier carrying a microorganism capable of flowing together with the anaerobic treated water to be treated is accommodated, and a carrier fluidizing tank for performing aerobic treatment with a diffuser for supplying bubbles to the carrier, and on the downstream side of the carrier fluidizing vessel, In a sewage treatment apparatus provided with a filtration tank having a sedimentation filtration layer formed in a state where a plurality of filtration carriers are settled and deposited inside, the to-be-processed water and sludge flowing out of the carrier fluidization tank are subjected to the carrier fluidization vessel. Sewage treatment equipment provided with a first advection mechanism that can be transferred to 2. An anaerobic treatment tank for anaerobically treating water to be treated,
The carrier carrying a microorganism capable of flowing together with the anaerobic treated water to be treated is accommodated, and a carrier fluidizing tank for performing aerobic treatment with a diffuser for supplying bubbles to the carrier, and on the downstream side of the carrier fluidizing vessel, In a sewage treatment apparatus provided with a filtration tank having a sediment filtration layer formed in a state where a plurality of filtration carriers are settled and deposited inside, between the carrier flow tank and the filtration tank, A separation unit is provided to prevent advection of the sludge in the carrier flow tank to the filtration tank, and to prevent the water to be treated and the sludge flowing out of the carrier flow tank from flowing into the carrier flow tank. A sewage treatment apparatus provided with a first advection mechanism that can be transferred to a tank. 3. The sludge treatment apparatus according to claim 1, further comprising a second advection mechanism capable of transferring the water to be treated and the sludge flowing out of the carrier fluidization tank to the anaerobic treatment tank. . 4. A backwashing device for removing sludge adhering to the filtration carrier, and controlling the transfer of water to be treated and sludge of the first advection mechanism and the second advection mechanism in accordance with the timing of backwashing. A method for operating a sewage treatment apparatus for operating a sewage treatment apparatus according to claim 3, further comprising a control mechanism for performing backwashing or removing the sludge attached to the filtration carrier. A method for operating a sewage treatment apparatus, comprising transferring treated water and sludge to the carrier fluidizing tank for a predetermined time, and transferring treated water and sludge from the filtration tank to the anaerobic treatment tank after a lapse of a predetermined time. 5. A backwashing device for removing sludge adhering to the filtration carrier, and controlling the transfer of the water to be treated and the sludge of the first advection mechanism and the second advection mechanism according to the timing of the backwashing. A method of operating a sewage treatment apparatus according to claim 3, further comprising a control mechanism that performs a backwashing or a backwashing to remove the sludge attached to the filtration carrier, at a predetermined rate, An operation method of a sewage treatment apparatus for transferring treated water and sludge in a filtration tank to the carrier fluidization tank and the anaerobic treatment tank.